Alarming prevalence of hepatitis-B infection among the Jarawas--a primitive Negrito tribe of Andaman and Nicobar Islands, India.

Jarawas, a classical hunter-gatherer tribe of Andaman and Nicobar islands have lived in isolation for several centuries. It is only recently have they started to come in contact with the outsiders, shedding their hostility. Since then, several disease outbreaks have been reported amongst them. Screening of sera samples collected during one such outbreak showed very high endemicity of hepatitis-B infection with over 60% of the individuals positive for hepatitis B surface antigen (HBsAg). The rates of HBsAg observed among the Jarawas are probably the highest ever reported in the world and warrant immediate control measures which would prevent further spread of this infection in the community.